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Decimal Constructor (Double)

Initializes a new instance of Decimal to the value of the specified double-precision floating-point number.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

public:
Decimal(
	double value
)

Parameters

value
Type: System::Double

The value to represent as a Decimal.

ExceptionCondition
OverflowException

value is greater than MaxValue or less than MinValue.

-or-

value is Double::NaN, Double::PositiveInfinity, or Double::NegativeInfinity.

This constructor rounds value to 15 significant digits using rounding to nearest. This is done even if the number has more than 15 digits and the less significant digits are zero.

The following code example creates several Decimal numbers using the constructor overload that initializes a Decimal structure with a Double value.

// Example of the Decimal( double ) constructor. 
using namespace System;

// Get the exception type name; remove the namespace prefix.
String^ GetExceptionType( Exception^ ex )
{
   String^ exceptionType = ex->GetType()->ToString();
   return exceptionType->Substring( exceptionType->LastIndexOf( '.' ) + 1 );
}


// Create a Decimal object and display its value. 
void CreateDecimal( double value, String^ valToStr )
{

   // Format and display the constructor.
   Console::Write( "{0,-34}", String::Format( "Decimal( {0} )", valToStr ) );
   try
   {

      // Construct the Decimal value.
      Decimal decimalNum = Decimal(value);

      // Display the value if it was created successfully.
      Console::WriteLine( "{0,31}", decimalNum );
   }
   catch ( Exception^ ex ) 
   {

      // Display the exception type if an exception was thrown.
      Console::WriteLine( "{0,31}", GetExceptionType( ex ) );
   }

}

int main()
{
   Console::WriteLine( "This example of the Decimal( double ) " 
   "constructor \ngenerates the following output.\n" );
   Console::WriteLine( "{0,-34}{1,31}", "Constructor", "Value or Exception" );
   Console::WriteLine( "{0,-34}{1,31}", "-----------", "------------------" );

   // Construct Decimal objects from double values.
   CreateDecimal( 1.23456789E+5, "1.23456789E+5" );
   CreateDecimal( 1.234567890123E+15, "1.234567890123E+15" );
   CreateDecimal( 1.2345678901234567E+25, "1.2345678901234567E+25" );
   CreateDecimal( 1.2345678901234567E+35, "1.2345678901234567E+35" );
   CreateDecimal( 1.23456789E-5, "1.23456789E-5" );
   CreateDecimal( 1.234567890123E-15, "1.234567890123E-15" );
   CreateDecimal( 1.2345678901234567E-25, "1.2345678901234567E-25" );
   CreateDecimal( 1.2345678901234567E-35, "1.2345678901234567E-35" );
   CreateDecimal( 1.0 / 7.0, "1.0 / 7.0" );
}

/*
This example of the Decimal( double ) constructor
generates the following output.

Constructor                                    Value or Exception
-----------                                    ------------------
Decimal( 1.23456789E+5 )                               123456.789
Decimal( 1.234567890123E+15 )                    1234567890123000
Decimal( 1.2345678901234567E+25 )      12345678901234600000000000
Decimal( 1.2345678901234567E+35 )               OverflowException
Decimal( 1.23456789E-5 )                          0.0000123456789
Decimal( 1.234567890123E-15 )       0.000000000000001234567890123
Decimal( 1.2345678901234567E-25 )  0.0000000000000000000000001235
Decimal( 1.2345678901234567E-35 )                               0
Decimal( 1.0 / 7.0 )                            0.142857142857143
*/

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0, 1.0

XNA Framework

Supported in: 3.0, 2.0, 1.0
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